amqtt/samples/client_subscribe.py

47 wiersze
1.4 KiB
Python

import logging
import asyncio
from amqtt.client import MQTTClient, ClientException
from amqtt.mqtt.constants import QOS_1, QOS_2
#
# This sample shows how to subscbribe a topic and receive data from incoming messages
# It subscribes to '$SYS/broker/uptime' topic and displays the first ten values returned
# by the broker.
#
logger = logging.getLogger(__name__)
async def uptime_coro():
C = MQTTClient()
await C.connect("mqtt://test.mosquitto.org/")
# Subscribe to '$SYS/broker/uptime' with QOS=1
await C.subscribe(
[
("$SYS/broker/uptime", QOS_1),
("$SYS/broker/load/#", QOS_2),
]
)
logger.info("Subscribed")
try:
for i in range(1, 100):
message = await C.deliver_message()
packet = message.publish_packet
print(
"%d: %s => %s"
% (i, packet.variable_header.topic_name, str(packet.payload.data))
)
await C.unsubscribe(["$SYS/broker/uptime", "$SYS/broker/load/#"])
logger.info("UnSubscribed")
await C.disconnect()
except ClientException as ce:
logger.error("Client exception: %s" % ce)
if __name__ == "__main__":
formatter = "[%(asctime)s] {%(filename)s:%(lineno)d} %(levelname)s - %(message)s"
logging.basicConfig(level=logging.INFO, format=formatter)
asyncio.get_event_loop().run_until_complete(uptime_coro())